Method and apparatus for monitoring oxygen concentration in beverage production process

ABSTRACT

The present invention continuously monitors the amount of oxygen dissolved in a beverage in a beverage storage tank in a beverage filler. Gas is continuously sampled via the vent holes  28  and the vent pipe  29  from the space part inside the beverage storage tank  1  of the beverage filler and is supplied to the oxygen measuring apparatus  40 . The oxygen measuring apparatus  40  includes the oxygen measuring device  45  and measures the concentration of oxygen gas of the delivered gas. Based on the concentration of oxygen gas, it is monitored whether or not the amount of oxygen dissolved in the beer inside the storage tank is at or below a predetermined level. Further, the beverage is sampled from a supply channel supplying the beverage to the beverage storage tank so that the concentration of oxygen in the beverage is measured and monitored.

TECHNICAL FIELD

The present invention relates to a method of monitoring oxygenconcentration in a production process of tea beverages or alcoholicbeverages including beer and an apparatus for executing the same.

BACKGROUND ART

The oxidation of tea beverages such as tea and green tea and alcoholicbeverages such as beer and sparkling liquor progresses with the passageof time after their production, so that their flavor graduallydeteriorates. This is mainly due to oxygen entering these beverages inthe process of their production. In the case of beer, for instance, ifonly an extremely small amount of oxygen enters the beer during itsproduction process, the oxygen molecules are partially reduced byelectrons transferred from metal (Fe, Cu) ions existing in the beer inits preserved state so that active oxygen is produced. The active oxygenoxidizes a variety of ingredients in the beer, such as isohumulone andalcohols, and generates aldehydes, which is the cause of aging odor,thereby deteriorating the flavor.

DISCLOSURE OF THE INVENTION

A variety of methods of reducing entry of oxygen in the productionprocess of beverages as much as possible have been studied as one ofmeasures to prevent the oxidation of beverages. In order to achievethis, it is necessary to constantly know the concentration of oxygen inthe production process, so that various studies have been conducted ofeffective timing and method of knowing.

It is an object of the present invention to provide a monitoring methodand apparatus for constantly monitoring the concentration of oxygen inreal time throughout the production process of beverages. By measuringand monitoring the amount of oxygen dissolved in a beverage immediatelybefore filling and the oxygen concentration of the vapor phase in astorage tank storing the beverage immediately before filling, an overallestimation of the effect of oxygen is made based on both of theconcentrations of oxygen.

The inventors of the present invention have focused on the amount ofoxygen dissolved in the beverage before filling in the productionprocess and the concentration of oxygen included, immediately beforefilling, in the vapor phase formed in the storage tank storing thebeverage.

The storage tank is internally occupied by the beverage to be filled andthe vapor phase of the space part, and the amount of oxygen dissolved inthe beverage is affected by the concentration of oxygen in the vaporphase.

That is, in this case, equilibrium is established between the liquidphase taken up by the beverage and the vapor phase of the space part.Therefore, if there is a difference in the concentration of oxygenbetween the phases, oxygen moves from the phase of high density to thephase of low density to cancel the difference in concentration, so thatthe concentrations converge into a state of equilibrium. Accordingly, ifthe concentration of oxygen in the vapor phase of the storage tank ishigher than the concentration of oxygen in the beverage, oxygen movesfrom the vapor phase into the beverage so that the amount of dissolvedoxygen is increased.

Normally, replacement is performed in the space part with gas that doesnot affect the flavor of the beverage, such as carbon dioxide ornitrogen gas. Accordingly, the quality of the gas to be supplied greatlyaffects the concentration of oxygen in the space part. Entry of oxygenmay occur if the gas supply system has a defect or a failure.

Further, in the case of filling a container with the beverage, thecontainer is filled with carbon dioxide or nitrogen gas, and thebeverage is filled into the container with the filling gas beingdischarged. Generally, the discharged filling gas is supplied into thestorage tank at this point. In this case, if replacement with thefilling gas is not fully performed inside the container due to themalfunction of a filling device, the filling gas having a large amountof oxygen remaining therein is delivered into the storage tank.

Further, even if the concentration of oxygen in the space part insidethe storage tank is low, entry of oxygen into the beverage occurringpreviously at the time of producing the beverage itself may be revealedin the form of an increase in the concentration of oxygen dissolved inthe beverage.

Thus, according to the present invention, the concentration of oxygen inthe vapor phase part inside the storage tank and the concentration ofoxygen dissolved in the beverage inside the storage tank are measured,and the effect of oxygen on the beverage is determined from bothconcentrations of oxygen.

Further, according to the present invention, the concentration of oxygenin the vapor part in the storage tank and the concentration of oxygenincluded in the beverage flowing through a supply channel supplying thebeverage to the storage tank are measured and monitored, and the effectof oxygen on the beverage is determined from both concentrations ofoxygen. Thereby, the concentration of oxygen dissolved into the beveragein the process of producing the beverage itself, which process isupstream from the filling process, and the concentration of oxygen inthe space part of the storage tank can be monitored respectively, sothat the process responsible for the entry of oxygen can be specified.

Further, as a system for constantly measuring and monitoring theconcentration of oxygen in the vapor phase of the space part inside thestorage tank in real time, an oxygen sensor may be attached directly tothe storage tank to measure the concentration of oxygen in the spacepart inside the tank, and the measured data (electrical signal) may bedisplayed on a determination apparatus or a display unit that isseparately provided externally. Alternatively, gas in the space partinside the storage tank may be discharged outside, and the concentrationof oxygen in the discharged gas may be measured by a measuring device tobe determined and displayed. As an oxygen concentration meter employedin this case, a measuring apparatus using a galvanic cell type oxygensensor, a zirconia type oxygen sensor, or a thermoparamagnetic oxygensensor may be employed.

Further, as a device for measuring the concentration of oxygen dissolvedin the beverage, the above-described oxygen concentration measuringapparatus using a sensor using a galvanic cell type oxygen sensor or azirconia type oxygen sensor is employed, and the sensor is attached tothe storage tank or the pipe channel supplying the beverage to thestorage tank.

If it is confirmed, as a result of measuring the concentration ofoxygen, that the concentration of oxygen exceeds a given allowablevalue, the beverage filling operation is stopped based on themeasurement information from the measuring apparatus, and a warning isissued. Alternatively, if the measurement reveals that the excess of theconcentration of oxygen over the given value is caused, for instance, bythe concentration of oxygen in the space part inside the storage tank,the primary cause of the increase in the concentration of oxygen can beimproved by increasing the supply of carbon dioxide or nitrogen gas tothe storage tank.

A mode of the present invention is a method of monitoring aconcentration of oxygen in a beverage production process, the methodcharacterized by including: a step of continuously sampling gas in aspace part inside a beverage storage tank storing a beverage to befilled, the beverage storage tank being provided to a beverage filler; astep of measuring a concentration of oxygen in the sampled gas; a stepof comparing the measured value and a preset first referenceconcentration; a first determination step of issuing an alarm signalwhen the measured concentration of oxygen exceeds the first referencevalue;

a step of continuously measuring a concentration of oxygen included inthe beverage inside the beverage storage tank; a second comparison stepof comparing the measured concentration of oxygen in the beverage with apreset second reference value; and a second determination step ofissuing an alarm signal when the measured concentration of oxygen in thebeverage exceeds the second reference value.

Another mode of the present invention is a method of monitoring aconcentration of oxygen in a beverage production process, the methodcharacterized by including: a step of continuously sampling gas in aspace part inside a beverage storage tank storing a beverage to befilled, the beverage storage tank being provided to a beverage filler; astep of measuring a concentration of oxygen in the sampled gas; a stepof comparing the measured value and a preset first referenceconcentration; a first determination step of issuing an alarm signalwhen the measured concentration of oxygen exceeds the first referencevalue;

a step of continuously measuring a concentration of oxygen included inthe beverage flowing through a beverage supply channel supplying thebeverage to the beverage storage tank storing the beverage to be filled,the beverage storage tank being provided to the beverage filler; asecond comparison step of comparing the measured concentration of oxygenin the beverage with a preset second reference value; and a seconddetermination step of issuing an alarm signal when the measuredconcentration of oxygen in the beverage exceeds the second referencevalue.

Yet another mode of the present invention is an apparatus for monitoringa concentration of oxygen in a beverage production process, theapparatus characterized by including: sampling means for continuouslysampling gas in a space part inside a beverage storage tank storing abeverage to be filled, the beverage storage tank being provided to abeverage filler; measuring means for measuring a concentration of oxygenin the sampled gas; comparison means for comparing the measured valueand a preset first reference concentration; first determination meansfor issuing an alarm signal when the measured concentration of oxygenexceeds the first reference value;

measuring means for continuously measuring a concentration of oxygenincluded in the beverage inside the beverage storage tank; comparisonmeans for comparing the measured concentration of oxygen in the beveragewith a preset second reference value; and second determination means forissuing an alarm signal when the measured concentration of oxygen in thebeverage exceeds the second reference value.

Yet another mode of the present invention is an apparatus for monitoringa concentration of oxygen in a beverage production process, theapparatus characterized by including: sampling means for continuouslysampling gas in a space part inside a beverage storage tank storing abeverage to be filled, the beverage storage tank being provided to abeverage filler; measuring means for measuring a concentration of oxygenin the sampled gas; first comparison means for comparing the measuredvalue and a preset first reference concentration; first determinationmeans for issuing an alarm signal when the measured concentration ofoxygen exceeds the first reference value;

measuring means for continuously measuring a concentration of oxygenincluded in the beverage flowing through a beverage supply channelsupplying the beverage to the beverage storage tank storing the beverageto be filled, the beverage storage tank being provided to the beveragefiller; second comparison means for comparing the measured concentrationof oxygen in the beverage with a preset second reference value; andsecond determination means for issuing an alarm signal when the measuredconcentration of oxygen in the beverage exceeds the second referencevalue.

Yet another mode of the present invention is an apparatus for monitoringa concentration of oxygen in a beverage production process, theapparatus characterized by including: a flow channel for gas in a spacepart inside a beverage storage tank for storing a beverage to be filledto flow through to outside the beverage storage tank, the beveragestorage tank being provided to a rotary beverage filler;

a distributor for receiving the gas from the flow channel and deliveringthe gas outside the beverage filler, the distributor being provided to arotating central shaft part of the beverage storage tank; an oxygenmeasuring device constantly measuring a concentration of oxygen in thegas delivered from said distributor; a delivery device for deliveringthe gas inside the space part to the oxygen concentration measuringdevice via the flow channel and the distributor; and a determinationdevice comparing the concentration of oxygen from the oxygenconcentration measuring device with a preset reference value and issuingan alarm signal when the measured value exceeds the reference value.

In the above-described modes of the present invention, the concentrationof oxygen in the vapor phase of the space part inside the beveragestorage tank and the concentration of oxygen included in the beverage inthe beverage storage tank are constantly monitored, and an alarm signalis issued when the concentrations of oxygen exceed the given referencevalues. Thereby, the quality of the beverage to be filled can constantlybe increased.

Further, in measuring and monitoring the concentration of oxygen in thevapor phase of the space part inside the beverage storage tank, the gascan be sampled continuously from the space part so that the alarm signalmay be issued when the given reference value is exceeded.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrative of a filling mechanism of a beerfiller;

FIG. 2 is a diagram illustrative of a storage tank of the beer filler;

FIG. 3 is a block diagram of a dissolved oxygen amount monitoring systemaccording to the present invention;

FIG. 4 is a diagram illustrative of a thermoparamagnetic oxygenmeasuring device; and

FIG. 5 is a diagram illustrative of a dissolved oxygen analyzer.

BEST MODE FOR CARRYING OUT THE INVENTION

A description will now be given of an embodiment in which the presentinvention is applied to the beer filling process of a production processof beer, referring to the drawings for a further detailed description ofthe present invention.

FIG. 1 shows a beer filler 1 to which the present invention is applied.The filler 1 includes an annular storage tank (filler bowl) 2. Aplurality of filling valves 3 are provided equally spaced on the bottompart of the storage tank 2. The filling valves 3 each include a liquidvalve 4 and a vent tube 5. The valve 4 operates so that liquid isinjected into a bottle 10 contacting a supply opening 6.

The bottle 10 to be injected with the liquid is transferred to andplaced on an elevating stand 11 provided below the storage tank 2. Theelevating stand 11 is elevated so that the bottle 10 has its mouthclosely contacting the supply opening 6. Reference numeral 12 denotes asupport member for positioning the bottle 10 to the supply opening 6.The bottle mount is positioned through a seal member 13. The supportmember 12 is supported by a sliding bar 14 sliding upward and downwardso as to move upward and downward in accordance with the upward anddownward movements of the bottle 10. Not shown in the drawing, thisembodiment is a rotary beverage filler, and filling of containers isperformed with the entire configuration of FIG. 1 being rotated about arotation axis not shown in the drawing.

FIG. 2 shows an upper structure of the beer filler 1. Various pipes areconnected via a distributor 21 to the upper part of the storage tank 2and the storage tank 2 so that the beer and gases are supplied theretoor discharged therefrom. As previously described, the beverage filler ofthis embodiment is a rotary filler, so that the storage tank 2 rotatesas well. Not shown in detail in FIG. 2, the storage tank 2 rotates in adirection of the arrow A about a central shaft M including thedistributor 21. Since the above-described pipes rotate with the storagetank 2, in order to take in or discharge the beer and the gases flowinginside the pipes from or to outside the filler, an interposing means forreceiving the flowing objects from the rotating pipes and supplying themto fixed vent pipes (or, in reverse, supplying the beer and gas suppliedfrom outside through fixed supply pipes to the rotating pipes) isrequired. The distributor 21 is provided as the interposing means.

The distributor 21 is provided in the central part of the annularstorage tank 2. A supply pipe 23 for supplying the beer is connected tothe distributor 21 from below, and a gas supply pipe 24 for supplyingcarbon dioxide or nitrogen gas is connected to the upper part of thedistributor 21. The beer supplied to the distributor 21 is supplied tothe storage tank 2 through twelve pipes 25. The gas supplied through thegas supply pipe 24, such as carbon dioxide or nitrogen gas, iscommunicated into the storage tank 2 from its upper wall through two gassupply pipes 26. Four vacuum pipes 27 penetrating the inner wall surfaceof the storage tank 2 are used for discharging gas from inside thecontainer (bottle) to be filled with the beer.

Two vent holes 28 for discharging gas from an upper space inside thestorage tank 2 are provided to the upper wall of the storage tank 2. Thevent holes 28 are connected to a vent pipe 29 via the distributor 21.The vent pipe 29 is connected to a later-described oxygen concentrationmeasuring apparatus.

Further, a dissolved oxygen analyzer 51 is attached inside the supplypipe 23 for supplying the beer so as to measure the amount of oxygendissolved in the supplied beer.

FIG. 3 is a schematic diagram for illustrating a dissolved oxygenmonitoring system according to the present invention. The vent pipe 29connected to the vent holes 28 provided to the storage tank 2 of thefiller 1 described in FIG. 2 is connected to an oxygen measuringapparatus 40 in order to measure the concentration of oxygen included inthe gas in the space part inside the storage tank. Carbon dioxide, whichis a replacement gas, is supplied to the storage tank 2 through thepipes 26 so that the upper space is filled with the carbon dioxide.

The oxygen measuring apparatus 40 includes a gas channel 41 connected tothe vent pipe 29 extending from the storage tank 2, and has a flowadjustment valve 42, a filter 43, a flowmeter 44, an oxygen measuringdevice 45, a flow adjustment valve 46, and a pump 47 sequentially alongthe gas channel 41.

By connecting the thus configured oxygen measuring apparatus 40 to thevent pipe 29 extending from the storage tank 2, the gas in the upperspace of the storage tank 2 is continuously introduced into the oxygenmeasuring apparatus 40, so that the concentration of oxygen included inthe gas can be measured. The measurement result obtained by the oxygenmeasuring device 45 can be constantly monitored by the display unit (notshown in the drawing) of the oxygen measuring device 45. In thisembodiment, however, the measurement result is transmitted to a dataprocessing apparatus 451 to be processed so that necessary informationcan be obtained. That is, the allowable level of the concentration ofoxygen gas included in the carbon dioxide is set beforehand as areference value and compared with a measurement value measured by theoxygen measuring device 45. It is determined that the amount of oxygenincluded in the space part inside the storage tank 2 exceeds theallowable level when the measurement value exceeds the reference value,and the determination result is displayed on a display unit 452. Insteadof a visual warning method shown in this embodiment, an auditory warningsuch as sound may be given based on a warning signal supplied from thedata processing apparatus 451, or production lines may be stopped.

The data processing apparatus 451 may be capable of calculating theconcentration of the carbon dioxide inside the storage tank 2, or a rateof replacement by the carbon dioxide in the space part inside thestorage tank, from the concentration of the oxygen gas included in thecarbon dioxide. In this case, the rate of replacement by the carbondioxide can be an index for monitoring the amount of oxygen included inthe space part inside the storage tank.

Here, the concentration of carbon dioxide is calculated from theconcentration of oxygen by the following equations:

Oxygen concentration÷0.209=amount of air  (1)

100−amount of air=carbon dioxide  (2)

A dissolved oxygen measuring sensor 51 measures the concentration ofoxygen dissolved in the beer flowing through the supply pipe 23. Theobtained measurement value is transmitted to the data processingapparatus 451 to be compared with a given level. When the value exceedsthe given level, an alarm signal is output to the display unit 452.

In this embodiment, a thermoparamagnetic oxygen sensor is employed asthe oxygen measuring device 45 used in the oxygen measuring apparatus40. Here, a description will be given of the principles of measurementof the thermoparamagnetic oxygen sensor.

The thermoparamagnetic oxygen sensor operates on the principle ofmagnetic wind. Unlike most other gases, oxygen is greatly affected by amagnetic field so as to be drawn to the central part of the magneticfield.

The influence of the magnetic field is inversely proportional totemperature. Therefore, when a sample gas including oxygen is heated,the influence of the magnetic field decreases. Accordingly, by heatingthe central part of the magnetic field, a drawn sample gas is driven outof the central part of the magnetic field by sample gas that is drawnsubsequently. Repetition of this generates flow (magnetic wind), whichdepends on the concentration of oxygen.

FIG. 4 is a diagram for illustrating gas flow inside the measurementchamber of the thermoparamagnetic oxygen sensor. A pair ofwind-generating-side and wind-receiving-side thermistors are provided ona magnet inside the measurement chamber. An electric current iscontrolled so that each thermistor is heated to a constant temperature.The influence of a magnetic field produced by the magnet on oxygen drawnto the magnetic field is decreased by the heated thermistors so thatflow is generated. This flow robs heat of the inner(wind-generating-side) thermistor so that the inner thermistor iscooled. The outer (wind-receiving-side) thermistor is warmed by the windthat has robbed the heat. The thermistors form a bridge circuit, and thebalance is varied by the flow. By measuring a variation in the balance,the concentration of oxygen can be measured. Therefore, by employing theabove-described thermoparamagnetic oxygen sensor in the oxygen measuringapparatus 40, the concentration of oxygen in the gas can be measuredwhile the gas is continuously introduced.

FIG. 5 shows an example of the dissolved oxygen measuring sensor 51employed in this embodiment. The dissolved oxygen measuring sensor 51used herein employs a polarographic amperometric method and haselectrodes formed of a cathode and an anode coupled by an electrolyte.As represented graphically, the dissolved oxygen sensor 51 is composedof a main body 511, a glass tube 512, an anode 513, a cathode 514, anelectrolyte 515, and a diaphragm 516 at the tip. The anode 513 and thecathode 514 are coupled by the electrolyte 515. Liquid to be examinedand the electrodes are separated by the diaphragm 516 that is agas-permeable film. Oxygen molecules passing through the permeable film516 are reduced by a polarographic potential applied to the cathode 514.At this point, an electric current proportional to the partial pressureof oxygen is generated. By measuring the electric current, the amount ofoxygen dissolved in the examined liquid can be measured.

Next, a description will be given, based on FIGS. 2 and 3, of an oxygenconcentration measuring and monitoring system used for the filler 1 ofthe present invention.

Beer to be filled into the bottles is supplied from the distributor 21to the storage tank 2 via the beer supply pipes 25.

As previously described, the filler is of a rotary type. As shown inFIGS. 1 and 2, the entire filler 1 including the storage tank 2 rotatesabout the central shaft M with the containers 10 circulatingaccordingly, while the beverage inside the storage tank 2 is filledthereinto through the filling valves 3. During this period, carbondioxide is supplied to the space part inside the storage tank 2 throughthe gas supply pipes 26 so as to replace air (oxygen) inside the spacepart.

As for the filling procedure of the beer, first, air inside thecontainers is discharged through the vacuum pipes 27, and then thecarbon dioxide is filled into the containers so as to replace the airtherein. After being filled with the carbon dioxide, the containers arefilled with the beer. The carbon dioxide that is discharged at thispoint is sent out into the storage tank 2.

In a series of the above-described beer filling operations, the gas inthe space part inside the storage tank 2 is sampled so that its oxygenconcentration is measured, while the concentration of oxygen dissolvedin the beer supplied to the storage tank 2 is measured. Based on both ofthe measured values, monitoring is performed so as to prevent oxygenfrom deteriorating the flavor of the beer.

Concerning monitoring of the concentration of oxygen in the gas in thespace part of the storage tank 2 in oxygen concentration monitoring bythe thus configured oxygen concentration measuring and monitoringsystem, the gas in the upper space of the storage tank 2 is suppliedfrom the vent holes 28 to the oxygen measuring apparatus 40 shown inFIG. 3 via the vent pipe 29. The gas introduced into the oxygenmeasuring apparatus 40 is adjusted to a given amount of flow by the flowadjustment valve 42 to be delivered to the oxygen measuring device 45via the filter 43 and the flowmeter 44. The oxygen measuring device 45,which is a thermoparamagnetic oxygen measuring device in thisembodiment, measures the concentration of oxygen in the gas suppliedcontinuously. The measurement value of the oxygen measuring device 45 ismonitored, and the concentration of oxygen in the gas is constantlymonitored by the display unit 452 showing the result of comparison withthe reference value in the data processing apparatus 451.

Further, in measuring the concentration of oxygen in the beer, theamount of oxygen dissolved in the beer is constantly monitored by havingthe concentration of dissolved oxygen measured constantly by thedissolved oxygen measuring sensor 51 and compared with a reference valuein the data processing part 451.

Thus, in the oxygen concentration measuring and monitoring system ofthis embodiment, the amount of oxygen included in the vapor phase of thespace part contacting the beer inside the storage tank can be measuredand monitored continuously, and the concentration of oxygen in the beerimmediately before filling can be monitored in real time.

In the above-described embodiment, in monitoring the concentration ofoxygen in the beer, the amount of dissolved oxygen is measured from thebeer inside the supply pipe 23 for supplying the beer to the storagetank 2. If the concentration of oxygen in the beer shows a value greaterthan the reference level by this, it can be understood that the cause ofoxygen dissolution lies in a process prior to the filling process. Inmeasuring the concentration of oxygen in the beer inside the storagetank, the beer may be sampled from inside the storage tank.

As described above, according to the present invention, the effect ofoxygen before filling containers with beer in the production processthereof can be measured and monitored, so that the beer can be preventedin advance from being produced with its flavor being deteriorated by theeffect of oxygen. Thereby, the best products having excellent flavordurability can always be produced.

In the above-described embodiment, the description is given of the casewhere a thermoparamagnetic oxygen sensor is employed as the oxygensensor of the oxygen measuring apparatus, while an oxygen sensor ofanother type, such as a galvanic cell type oxygen sensor, may beemployed. However, if the main component of gas to be measured is carbondioxide as the gas of the above-described embodiment, thethermoparamagnetic oxygen sensor, which is less subject to deteriorationby carbon dioxide, is superior.

Another type of dissolved oxygen analyzer than that shown in FIG. 5 isalso employable.

In the above-described embodiment, the description is given of anapparatus for monitoring the amount of oxygen dissolved in the beerinside the storage tank of the beer filler, while, needless to say, thepresent invention is applicable to fillers of beverages other than beer,such as tea beverages including tea and green tea and alcoholicbeverages including sparkling liquor.

Further, carbon dioxide is described as a replacement gas to replace thegas inside the storage tank, while another gas such as nitrogen gas isapplicable as the replacement gas.

EFFECTS OF THE INVENTION

As is apparent from the above detailed description, according to thepresent invention, the amount of oxygen, which affects the flavor of abeverage, is constantly measured and monitored immediately before thebeverage is filled into beverage containers, and a warning is issuedwhen it is determined that the amount of oxygen reaches a level whereits effect is not negligible. Therefore, the beverage is prevented inadvance from being filled with oxygen included therein, so that beverageproducts having excellent flavor durability can be provided.

Further, in a rotary beverage filler, gas in a space part inside abeverage storage tank can be sampled continuously from the rotatingbeverage tank through a distributor provided in the rotation center partof the beverage storage tank so that the concentration of oxygen in thegas can be continuously monitored.

What is claimed is:
 1. A method of monitoring a concentration of oxygenin a beverage production process, the method characterized by comprisingthe steps of: (a) continuously sampling gas in a space part inside abeverage storage tank storing a beverage to be filled, the beveragestorage tank being provided to a beverage filler; (b) measuring aconcentration of oxygen in the sampled gas; (c) comparing the measuredconcentration of oxygen in the sample gas and a preset first referenceconcentration; (d) issuing an alarm signal when the measuredconcentration of oxygen in the sampled gas exceeds the first referencevalue; (e) continuously measuring a concentration of oxygen included inthe beverage inside the beverage storage tank; (f) comparing themeasured concentration of oxygen in the beverage with a preset secondreference value; and (g) issuing an alarm signal when the measuredconcentration of oxygen in the beverage exceeds the second referencevalue.
 2. An apparatus for monitoring a concentration of oxygen in abeverage production process, the apparatus comprising: a sampling partcontinuously sampling gas in a space part inside a beverage storage tankstoring a beverage to be filled, the beverage storage tank beingprovided to a beverage filler; a first measuring part measuring aconcentration of oxygen in the sampled gas; a first comparison partcomparing the measured concentration of oxygen in the sampled gas and apreset first reference concentration; a first determination issuing analarm signal when the measured concentration of oxygen in the sampledgas exceeds the first reference value; a second measuring partcontinuously measuring a concentration of oxygen included in thebeverage inside the beverage storage tank; a second comparison partcomparing the measured concentration of oxygen in the beverage with apreset second reference value; and a second determination part issuingan alarm signal when the measured concentration of oxygen in thebeverage exceeds the second reference value.
 3. The apparatus as claimedin claim 1, further comprising: a flow channel for the sampled gas toflow through to an outside of the beverage storage tank; a distributorfor receiving the sampled gas from the flow channel and delivering thesampled gas to said first measuring part outside the beverage filler,wherein said first measuring part constantly measures the concentrationof oxygen in the sampled gas.
 4. The apparatus as claimed in claim 3,wherein said distributor is provided to a rotary center shaft of thebeverage storage tank provided to the beverage filler, the beveragefiller being of a rotary type.